Android经常使用UI组件

TextView是Android里面用的最多的UI组件，一般使用在须要显示一些信息的时候，其不能输入，仅仅能初始设定或者在程序中改动。

实例：TextViewDemo

执行效果：

代码清单：

布局文件：main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="这里是TextView，你能够在这里显示一些文本信息。"
    />
</LinearLayout>

Java源码文件：MainActivity.java

package com.rainsong.textviewdemo;

import android.app.Activity;
import android.os.Bundle;

public class MainActivity extends Activity
{
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}

API知识点

Activity

public class

Activity

extends ContextThemeWrapper

implements ComponentCallbacks2 KeyEvent.Callback LayoutInflater.Factory2 View.OnCreateContextMenuListener Window.Callback

Known Direct Subclasses

AccountAuthenticatorActivity, ActivityGroup, AliasActivity, ExpandableListActivity, FragmentActivity, ListActivity, NativeActivity

Known Indirect Subclasses

LauncherActivity, PreferenceActivity, TabActivity

void setContentView(int layoutResID)

Set the activity content from a layout resource.

TextView

public class

TextView

extends View

implements ViewTreeObserver.OnPreDrawListener

Known Direct Subclasses

Button, CheckedTextView, Chronometer, DigitalClock, EditText, TextClock

Known Indirect Subclasses

AutoCompleteTextView, CheckBox, CompoundButton, ExtractEditText, MultiAutoCompleteTextView, RadioButton, Switch, ToggleButton

Class Overview

Displays text to the user and optionally allows them to edit it. A TextView is a complete text editor, however the basic class is configured to not allow editing; see EditText for a subclass that configures the text view for editing.

Public Constructors

TextView(Context context)

TextView(Context context, AttributeSet attrs)

TextView(Context context, AttributeSet attrs, int defStyle)